The earth (mass `=6xx10^(24)kg`) revolves round the sun with an angular velocity of `2xx10^(-7)"rad/s"` in a circular orbit of radius `1.5xx10^(8)km.` The gravitational force exerted by the sun on the earth, in newtons, is

Options

A. Zero N
B. `18xx10^(25)N`
C. `27xx10^(39)N`
D. `36xx10^(21)N`

Answer

D

Explanation

The force exerted by the sun on the earth is the gravitational force given by
`F=(GMm)/(R^(2))=(mv^(2))/(r )= mr omega^(2)`
`therefore F = mr omega^(2)`
`= 6xx10^(24)xx1.5xx10^(8)xx10^(3)xx2xx10^(-7)xx2xx10^(-7)`
`therefore F = 36xx10^(21)N`